The present invention relates to a stuffing apparatus and method and more particularly to means and method for making fine adjustments to casing holdback.
Casing holdback is one factor which should be controlled in order to stuff a casing to a desired diameter. In general terms, the casing will be more fully stuffed as casing holdback increases. Since casings of the same size may not necessarily exhibit similar stuffing characteristics, an adjustable holdback force is desired so that small changes can be made to insure that the casing is stuffed out to a given diameter.
In some automatic operations there is even provision for applying and releasing a holdback force at selected times in the sutffing cycle. For example, holdback force is applied to the casing during stuffing and then is released in order to facilitate the gathering and closing of the casing over the trailing end of the stuffed product. In these automatic operations control of the limits of the holdback force is desirable to insure that when the holdback force is applied, it is not more or less than the desired amount.
The present invention provides a means to quickly and easily accomplish small adjustments to the holdback force. In particular the present invention is adapted to make such an adjustment in stuffing apparatus wherein the holdback force is provided by cooperation of a sizing member within the casing and an external casing contacting member outside the casing.
Typically, such apparatus, as shown for example in U.S. Pat. Nos. 4,007,090 and 4,164,057, has a sizing member within the casing which contacts the inner surface of the casing as the casing is drawn over the sizing member. An external casing contacting member, usually a snubbing ring which is placed about the exterior of the casing, turns the casing inwardly as it is drawn over the internal sizing member. The axial or longitudinal distance between the snubbing ring and sizing member contributes to the magnitude of the total casing holdback force. In the method and apparatus of the present invention, provision is made for fine adjustment of the closest spacing of the internal and external casing contacting members to control the magnitude of the casing holdback force.
In stuffing apparatus, there also is usually an emulsion seal which snugs the casing to the stuffing horn adjacent to the discharge of the stuffing horn. This seal prevents the product being stuffed from backflowing around the end of the stuffing horn. The present invention permits incorporation of such an emulsion seal into a common fixture with the external casing contacting member. Even though the external casing contacting member and emulsion seal are on a common fixture, the present invention, nevertheless allows movement of the external casing contacting member relative to the emulsion seal so that any adjustment of the casing contacting member will not disrupt the location of the emulsion seal from its position at the discharge end of the stuffing horn. Conversly, in the present invention, the emulsion seal can be located at a desired position relative to the discharge end of the stuffing horn and the external casing contacting member can be adjusted without changing the emulsion seal position.